83VR, fuel gauge flickers level then goes off

[Droneh8tr]

My fuel level indicator flickers a 2 bar level when the key is turned to ON, but then nothing and of course I get the flashing warning light.

I've soldered the circuit board behind the instrument panel, I've cleaned the contacts on the sensor float, and the plug behind the headlight. I've checked the wiring to make sure it's not going to ground or something..

I also measureded the resistance on the sensor and I'm getting 30 ohms.

 

What else can I try or do?

The indicator used to work, but has been slowly being more and more intermittent to non existent.

[Prairiehammer]

Barring any intermittent ground or loose connection, the fuel level sensor should read 30Ω or less when tank is full, 160-180Ω when half full and 300Ω or more when tank is empty.

 

As you see, if a connection is lost, the CMS thinks that the fuel tank is empty (300Ω+).

 

I would revisit all the points you checked before, paying particular attention to the green/white wire and it's associated connections.

 

Cleaning the fuel level sensor requires removing the metal box around the resistance coil. If you did so, make sure that you didn't inadvertently ground the resistance coil. Also double check that the resistance coil in the fuel sensor is making good contact to the wiper throughout the range of the float arm. Confirm that the fuel level sensor indicates the above noted readings. There have been instances where the fuel level sensor resistance coil armature is deformed. The result is an apparent empty fuel tank.

 

Examine again the ohm readings through out the range. It should be linear.

[jasonm.]

cleaning is done by lightly using 1000 paper between the "wiper" and the sender coil where they meet. If this does not make sense. Then you may have not cleaned the sender. Do you have 30 ohms when full...that's good. But I had the same issue when 1/2 full and the cleaning I describe cured it. Otherwise you have a loose wire by/to the sensor. Also lightly bending the wiper against the coil...makes a positive connection. Careful...it's sensitive area.

[Droneh8tr]

Barring any intermittent ground or loose connection, the fuel level sensor should read 30Ω or less when tank is full, 160-180Ω when half full and 300Ω or more when tank is empty.

 

As you see, if a connection is lost, the CMS thinks that the fuel tank is empty (300Ω+).

 

I would revisit all the points you checked before, paying particular attention to the green/white wire and it's associated connections.

 

Cleaning the fuel level sensor requires removing the metal box around the resistance coil. If you did so, make sure that you didn't inadvertently ground the resistance coil. Also double check that the resistance coil in the fuel sensor is making good contact to the wiper throughout the range of the float arm. Confirm that the fuel level sensor indicates the above noted readings. There have been instances where the fuel level sensor resistance coil armature is deformed. The result is an apparent empty fuel tank.

 

Examine again the ohm readings through out the range. It should be linear.

I will remove the sender again and clean/adjust/ measure and insure contact along its entire length again. It seemed to be working fine the last time.

 

cleaning is done by lightly using 1000 paper between the "wiper" and the sender coil where they meet. If this does not make sense. Then you may have not cleaned the sender. Do you have 30 ohms when full...that's good. But I had the same issue when 1/2 full and the cleaning I describe cured it. Otherwise you have a loose wire by/to the sensor. Also lightly bending the wiper against the coil...makes a positive connection. Careful...it's sensitive area.

Your right about it being a sensitive area. Them wires are fine.... I did lightly sand the entire length of the contact area and my ohms go up an down.

 

Would one of you please do this for me.....

Turn your key to the ON position while watching the fuel gauge.. Do you immediately get a fuel level? Does it flash a fuel level (if so, how much). When do you get a proper fuel level indication.

I'm focusing on the flicker of fuel level I get. This seems like an indication that could point to my problem. Maybe I need to recheck my soldering job?? Or maybe resolder other connections on the circuit board. I soldered the 2 rows that was recommended. Is their something else that I should solder?

[jasonm.]

the least likely is the circuit board unless the bike is always parked outside and weather on.>>>>>>>> 90% of the time the simplest solution is it... BAD connection somewhere close to the source..sender. Fuel gauge immediately(2 sec.or less) reads correctly when the key is on.. Check the external wires directly at the sender. Yes they are thin. The ground wire can get beaten up . Clean the ground wire connection. 1000 paper or fine steel wool or mothers polish

[Prairiehammer]

Would one of you please do this for me.....

Turn your key to the ON position while watching the fuel gauge.. Do you immediately get a fuel level? Does it flash a fuel level (if so, how much). When do you get a proper fuel level indication.

 

On my Venture there is no delay. The fuel gauge immediately shows the actual level when the ignition is switched on. No flickering. No fluctuating. Currently my tank shows three bars.

[jasonm.]

i really don't look at the gauge much...so yes, right away while the computer monitor system checks all the safety sensors...brake fluid , etc.

[Neil86]

Another test might be to fab up a jumper wire with a 160-180 ohm resistor

and connect it in place of the sender.....does the CMS indication remain steady

around 1/2 tank...if so its in the sender...if not theres issues at CMS end.

 

Even though full the resistance is 30 ohms I don't recommend jumpering with no resistor

it might not hurt anything, but rather play it safe.

[Droneh8tr]

Another test might be to fab up a jumper wire with a 160-180 ohm resistor

and connect it in place of the sender.....does the CMS indication remain steady

around 1/2 tank...if so its in the sender...if not theres issues at CMS end.

 

Even though full the resistance is 30 ohms I don't recommend jumpering with no resistor

it might not hurt anything, but rather play it safe.

 

Thanks all for giving me ideas..

I did jump the plug end with a resistor. NO CHANGE... The gauge flickers on with 2 bars, goes off and that's it..

I was thinking something on the CMS end also, but I don't know what else I can do to it. I soldered the two rows inside the CMS. Is their anything else that should be soldered?

[Neil86]

Maybe test resistance to sender at unhooked connector on CMS....in case theres a bad wire in betwixt.

[Droneh8tr]

problem solved

The solder on the CMS for the fuel level wasn't making contact.... Resoldered and all is good now.

Thanks to everyone who responded

[venturesome]

Just had the same problem! Soldered all connector pins on CM and re-installed with no results. After a lot of frustration, decided to solder again, but more aggressively. I felt that I had nothing to lose, so I re-soldered with more heat and more solder, but careful not to short circuits on board. It now works fine.

[Droneh8tr]

Just had the same problem! Soldered all connector pins on CM and re-installed with no results. After a lot of frustration, decided to solder again, but more aggressively. I felt that I had nothing to lose, so I re-soldered with more heat and more solder, but careful not to short circuits on board. It now works fine.

 

Excellent.. as you read, I did the exact same thing.

[venturesome]

I know, you were my inspiration to try it again. THANKS!